1. Technical Field of the Invention
This invention relates to a tubular container with a tamper-proof cap, based on a container tube and a cap, on which the tube has an externally screw threaded hollow neck, onto which an internally screw threaded cylindrical portion of the cap fits.
In the interior of its hollow neck, the tube is provided with a portion of wall provide with holes to allow material to pass through, from the base of which and extending towards the exterior is a blind projection that continues to the open cavity in the central top surface of the cap, giving it access to the exterior so that the product contained in the tube can be applied or taken.
The cap has an outer skirt that closes over the tube, as well as an inner skirt which adjusts tightly against the internal wall of the screw threaded neck of the tube so as to make it leakproof and prevent the undesired exit of the product between both.
In the same way, the cap and tube are provided with the corresponding means to witness that the assembly is tamper-proof, as described in EP-A-0 410 922 belonging to the same applicant.
2. Prior Art
In equal conditions, and as suggested in EP-A-0 520 118, also belonging to the same applicant, the tube and cap have the corresponding means, a flexible projection on the tube and a rigid internal projection on the cap, which make contact when the cap is turned in one direction or the other, so that a characteristic noise is emitted.
In tubular containers of this kind, the blind projection that comes from the tube and adjust to the hole in the top surface of the cap is hollow and of a considerable diameter, and its free end is flat or slightly outwardly concave so that it can adjust to the usually concave shape of the said top surface of the cap.
The excessive diametrical dimension of the protuberance that forms the blind projection makes it necessary to use ingates of the appropriate dimensions in the injection process for this part and, as a result, prolonged cooling times which, in short, make both the procedure and the product more expensive.
Moreover, once the cooling period has passed, it is necessary to proceed and cut the free end of the blind projection created, which, in addition to meaning another operation, also includes the possibility of burrs appearing on the said projection.
As the result of all this, when the tube and cap unit is fully assembled, it is awkward to a certain extent for the user to use the product that comes out of the top surface of the cap.
A second disadvantage that also often occurs in practice is the lack of leak tightness between the surfaces of the inner skirt and the also internal surface of the neck of the tube, which, as they are flat, do not totally ensure that the product contained in the tube does not leak through this space accidentally.
On the other hand, in the said tubular containers, the sound warning between the cap and the tube is subject to certain limitations as regards intensity, due to the fact that the part that flexes is part of the tube itself, which on occasions leads to the limited generation of a sound signal.